The study is relevant to British people because Islamic integration is assumed to work better in America than in Europe.

Messrs Kedar and Yerushalmi ask two basic questions: first, whether there is a link between sharia-adherent behaviour in American mosques and the making available of books and videos sanctioning violence; and second, whether there is a link between violent materials in a mosque and that mosque’s leaders advocating violent or supremacist behaviour?

The researchers appear to have been sampled cautiously and impartially. Data came from a random, representative sample of 100 US mosques in 14 states, plus the District of Columbia:

A surveyor visited a subject mosque in order: (a) to observe and record 12 Sharia-adherent behaviors of the worshipers and the imam (or lay leader); (b) to observe whether the mosque contained the selected materials rated as moderate and severe; (c) to observe whether the mosque contained materials promoting, praising, or supporting violence or violent jihad; and (d) to observe whether the mosque contained materials indicating the mosque had invited guestspeakers known to have promoted violent jihad.

The Sharia-adherent behaviour was selected for its significance according to “Reliance of the Traveller”, “Fiqh as-Sunna”, and other standard – if unsavoury – sharia discourses:

Among the behaviors observed at the mosques and scored as Shari’a-adherent were: (a) women wearing the hijab (head covering) or niqab(full-length shift covering the entire female form except for the eyes); (b) gender segregation during mosque prayers; and (c) enforcement of straight prayer lines. Behaviors that were not scored as Shari’a-adherent included: (a) women wearing just a modern hijab, a scarf-like covering that does not cover all of the hair, or no covering; (b) men and women praying together in the same room; and (c) no enforcement by the imam, lay leader, or worshipers of straight prayer lines.

The moderate-rated literature was authored by respected Shari’a religious and/or legal authorities; while expressing positive attitudes toward violence, it was predominantly concerned with the more mundane aspects of religious worship and ritual. The severe material, by contrast, largely consists of relatively recent texts written by ideologues, rather than Shari’a scholars, such as Abul Ala Mawdudi and Sayyid Qutb. These, as well as materials published and disseminated by the Islamist Muslim Brotherhood, are primarily, if not exclusively, aimed at using Islam to advance a violent political agenda.

This choice of materials seem to have been chosen because they “are not Islamic legal texts per se but rather are polemical works seeking to advance a politicized Islam through violence, if necessary. Nor are these authors recognized Shari’a scholars.”

The results of the survey were unambiguous: most mosques offered pro-violence materials, but the mosques most likely to do so were the ones encouraging sharia-adherent behaviour.

The survey’s findings, explored in depth below, were that 51 percent of mosques had texts that either advocated the use of violence in the pursuit of a Shari’a-based political order or advocated violent jihad as a duty that should be of paramount importance to a Muslim; 30 percent had only texts that were moderately supportive of violence like theTafsir Ibn Kathir and Fiqh as-Sunna; 19 percent had no violent texts at all.

And:

The study found a statistically significant association between the severity of violence-positive texts on mosque premises and Shari’a-adherent behaviors.

In addition mosques containing severe material were likely actively to encourage terrorism and the funding of it:

The survey found a strong correlation between the presence of severe violence-promoting literature and mosques featuring written, audio, and video materials that actually promoted such acts. By promotion of jihad, the study included literature encouraging worshipers to engage in terrorist activity, to provide financial support to jihadists, and to promote the establishment of a caliphate in the United States. These materials also explicitly praised acts of terror against the West; praised symbols or role models of violent jihad; promoted the use of force, terror, war, and violence to implement the Sharia; emphasized the inferiority of non-Muslim life; promoted hatred and intolerance toward non-Muslims or notional Muslims; and endorsed inflammatory materials with anti-U.S. views… [O]f the 51 mosques that contained severe materials, 100 percent were led by imams who recommended that worshipers study texts that promote violence.

And there doesn’t seem to be much difference between moderate and severe mosques when it comes to violence against the infidel.

[M]osques containing violence positive materials were substantially more likely to include materials promoting financial support of terror than mosques that did not contain such texts. A disturbing 98 percent of mosques with severe texts included materials promoting financial support of terror. Those with only moderate rated materials on site were not markedly different, with 97 percent providing such materials.

These results were comparable when using other indicators of jihad promotion. Thus, 98 percent of mosques that contained severe-rated literature included materials promoting establishing an Islamic caliphate in the United States as did 97 percent of mosques containing only moderate rated materials.

Remember this if you thought that you would only be concerned about a mosque in your neighbourhood if it was run by members of the small minority of unrepresentative extremists. The moderate mosque may not attract violence, but it’s just as likely to encourage it.

Depressing stuff. But what makes the picture even worse is the number of people coming to hardline mosques compared to moderate ones:

Mosques that contained written materials in the severe category were the best attended, followed by those with only moderate-rated materials, trailed in turn by those lacking such texts. Mosques with severe materials had a mean attendance of 118 worshipers while mosques containing only moderate materials had a mean attendance of 60 worshipers; mosques that contained no violence-positive literature had a mean attendance of 15 worshipers.

Read that last paragraph again. Do the arithmetic. Nearly three quarters of mosque-goers attend ‘severe’ (offering modern materials with a violent political axe to grind) mosques; just over one fifth go to moderate (predominantly worship and ritual with some positive attitudes towards violence) mosques; and 3.5%, or one in thirty, go to mosques with no violent materials in them.